
1451
2-Wire and 4-Wire 
Ionization Smoke Detector
General
The System Sensor 400 Series plug-in ionization smoke 
detectors respond quickly to both fast flaming and slow smoldering fires as required by UL 268. Unipolar dual chamber 
sensor has the sensitivity needed to quickly detect smoke, and 
the stability needed to avoid false alarms.
Features
• Unique dual unipolar sensor:
– Provides exceptional stability. 
– Factory preset at 1.9% nominal sensitivity. 
– Stable operation up to 1,200 feet per minute (6 meters per
second) air velocities.
• Removable cover for field cleaning.
• Two visible LEDs “blink” in standby.
• Sealed against dirt, insects, and back pressure.
• Three-year limited warranty.
• Field metering of detector sensitivity.
• Built-in test switch.
• Low standby current.
• Built-in tamper-resistant feature.
• Designed for direct surface or electrical box mounting.
• 360° field viewing angle of the visual alarm LEDs.
• Insect-resistant screening (0.020"/0.508 mm openings).
• Easy plug-in of the head to base.
• SEMS screws for easy wiring.
• Optional recess mounting.
• Field-adjustable sensitivity.
Applications
Use to contribute to life safety, fire protection, and property 
conservation. Superior to photoelectric detectors in detecting 
fast-flaming fires. Superior to bipolar detectors in avoiding 
false alarms.
Construction & Operation
All 400 Series plug-in ionization smoke detectors contain a 
unique dual-source, dual unipolar chamber detection design 
which will sense the presence of smoke particles produced by 
fast combustion as well as slow smoldering fires. Additional 
key features include a blinking LED standby status indicator, 
an easily visible alarm indication, and provision for convenient 
field test and metering.
The back of the detector is sealed to block back-pressure air 
flow. The chamber is protected by a fine mesh (0.020"/0.508 
mm) screen to minimize problems with dust, dirt, and insects. 
If cleaning is required, it is easy to remove the cover (with a 
special tool) and obtain access to the screen and chamber to 
perform a thorough cleaning.
Installation
Model 1451 detectors are intended for use with Notifier ULlisted control panels. Maximum number of detectors per zone 
is listed in the installation manual for each control panel. Easy
DN-1154:A • I-110
Conventional Initiating Devices
1154pho.jpg
1451
Ionization Detector shown with B401B Base
to install and maintain, this detector is designed for direct surface mounting (using one of the B400 Series bases listed 
below). Easy-to-wire screw terminals allow fast and simple 
field wiring of IN, OUT, and remote annunciator connections.
Consult Notifier control panel specifications for the maximum 
allowable loop resistance for the particular control panel to be 
used.
To prevent wiring mistakes, observe polarities and make certain that each conductor is identifiable. A copy of Installation 
and Maintenance Instructions is packaged with each detector. For further information, refer to NFPA 72 “Standard on 
Automatic Fire Detectors.”
A Mounting Base Selection Guide is included on page 2 of 
this document.
Junction Box Selection Guide: Box depth is contingent on 
base and wire size. Refer to National Electrical Code or local 
applicable codes for appropriate recommendations. Bases 
B401 and B401B can utilize a single-gang, 3-1/2" (88.9 mm) 
octagonal, 4" (101.6 mm) octagonal, or 4" square junction box. 
Bases B402B and B406B can utilize a single-gang, 3-1/2" 
octagonal, 4" octagonal, 4" square, 50 mm, 60 mm, or 75 mm 
junction box. Base B404B can utilize a 4" octagonal or 4" 
square junction box.
General Specifications
Operating voltage: mounting base dependent (see chart 
below).
Standby current: 120 micro amps.
Sensitivity: 1.9% nominal.
Weight: 0.6 pounds (272 grams).
Size: 3.2" (81.28 mm) high; 4.0" (101.6 mm) diameter with
unflanged bases, or 6.2" (157.48 mm) diameter with flanged 
bases.
Construction: Flame-retardant white Noryl® plastic.
Temperature: 32°F to 120°F (0°C to 49°C).
DN-1154:A • 6/4/08 — Page 1 of 4
 

Humidity range: 10 to 93% R.H. (non-condensing).
Maximum air velocity: 1,200 feet per minute (6 meters per 
second).
Agency Listings and Approvals
These listings and approvals apply to the modules specified in 
this document. In some cases, certain modules or applications 
may not be listed by certain approval agencies, or listing may 
be in process. Consult factory for latest listing status.
• UL Listed: S911
• ULC Listed: S911 (1451A)
• MEA Listed: 427-91-E Vol. III
• FM Approved
• CSFM: 7271-1653:108
• BSA: 1202-88-SA
• Maryland State Fire Marshal Certificate: #2185
Product Line Information
1451: Ionization Detector. Must be mounted to one of the 
B400 Series Bases listed below.
RA400Z: Remote Annunciator for 2- or 4-wire applications. 
Use with any System Sensor 400 Series plug-in detector. Fits 
standard U.S. single-gang electrical box.
MOD400R: Field Test module for all of the System Sensor 
400 Series Smoke Detectors.
B401(B) Wiring Diagram
B402B Wiring Diagram
5578d1.wmf
5578d4.wmf
5578d3.wmf
B406B Wiring Diagram
B404B Wiring Diagram
Mounting Base Selection Guide
Base 
Model 
Number 
Version
Loop 
Type
(A)
B401 & 
B401B (A)
B402B (A) UL & ULC 4-wire Yes Form-A & -C 24 VDC
B404B (A) UL & ULC 4-wire Yes
B406B (A)
* Functionality contingent on panel compatibility. 
** Must be limited by control panel. 
Relay Contact Ratings: Resistive or Inductive (60% power factor load). Form-a: 2.0A at 30VAC/DC. 
Form-C: 0.6A at 110VDC, 2.0A at 30VDC, 1.0A at 125 VAC. 
(A) = ULC model designation.
UL/ULC/ 
EN-54
UL/ULC/ 
EN-54
2-wire* No - 12/24 VDC
2-wire* No Form-C 24 VDC
Current 
Limit 
Resistor
Alarm 
Contact 
Type
Form-A & -C/A 
Supervisory
Nominal 
Voltage
120 VAC 120 VAC
Standby 
Voltage
8.5 to 35 
VDC
17 to 32 
VDC
15 to 32 
VDC
Current 
Draw on 
Alarm
10 to 100 
mA**
14 to 39 
mA
75 mA AC 
maximum
12 to 100 
mA**
5578d2.wmf
Location of 
holes to 
access and 
release 
locking 
prongs.
Cover and 
screen are 
removable 
for cleaning.
Locking 
prongs.
1154d1.tif
Page 2 of 4 — DN-1154:A • 6/4/08
 

Page 4 of 4 — DN-1154:A • 6/4/08
NOTIFIER® is a registered trademark of Honeywell International Inc. Noryl® 
is a registered trademark of GE Plastics, a subsidiary of General Electric 
Company. 
©2008 by Honeywell International Inc. All rights reserved. Unauthorized use 
of this document is strictly prohibited.
This document is not intended to be used for installation purposes.
 We try to keep our product information up-to-date and accurate. 
We cannot cover all specific applications or anticipate all requirements. 
All specifications are subject to change without notice.
For more information, contact Notifier. Phone: (203) 484-7161, FAX: (203) 484-7118.
www.notifier.com
Made in the U.S. A.